Rollover protective systems for construction vehicles

ABSTRACT

Protection against injury to an operator of a construction vehicle in the event of rollover is provided by a system which may be adapted to many different types of construction vehicles, yet which will withstand the static tests accepted as the industry standard for simulating rollover. The system includes an integral superstructure including upright corner column members joined at their upper ends by longitudinal and transverse horizontal members. At each upper corner of the superstructure there is a special gusset member interconnecting the three coincident superstructure members. The gusset members effect a smooth transition of stress applied to one member to the other members of the superstructure with minimum deflection. The bases of the superstructure upright columns are anchored by means of vibration mounts to brackets which are attached to the vehicle frame.

llnited States Patent 1 Moore et a1.

[ Jan. 115, 197$ ROLLOVER PROTECTIVE SYSTEMS FOR CONSTRUCTION VEHICLES[75] Inventors: James C. Moore, Clackamas; Milton K. Leonard, LakeOswego, both of Oreg.

[73] Assignee: Portland Wire & Iron Works,

Portland, Oreg.

[22] Filed: Nov. 19, 1971 [21] Appl' No.: 200,302

[52] US. Cl 296/102, 52/280, 287/l89.36 R [51] Int. Cl. B60j/7/24 [58]Field of Search 296/102;

280/150 C; 287/l89.36 R; 52/280 [56] References Cited UNITED STATESPATENTS 3,632,134 l/l972 Babbitt 280/150 C 3,036,858 5/1962 Fingerut296/102 3,455,598 7/1969 Tweedy 296/102 Primary ExaminerRobert R. SongAttorney-James J. Hill [5 7] ABSTRACT tion of stress applied to onemember to the other members of the superstructure with minimumdeflection. The bases of the superstructure upright columns are anchoredby means of vibration mounts to brackets which are attached to thevehicle frame.

7 Claims, 18 Drawing Figures PATENTED JAN-l 51974 6\ w H 3 2 I PATENTED3,785,696

SHEEI 6 [IF 8 PATENTEUJAN15'974 3,785,696

' SHEEI 7 (If a ROLLOVER PROTECTIVE SYSTEMS FOR CONSTRUCTION VEHICLESBACKGROUND AND SUMMARY Certain types of construction equipment such asloaders, tractors, graders, bulldozers, compactors and scrapers(collectively referred to as tractors herein) are operated underconditions wherein it is possible that the equipment will roll over.Such a condition is obviously extremely hazardous to the operator, andit has therefore become highly desirable to provide protection to theoperator in the event of rollover. As an absolute minimum, anyprotective system should be of sufficient strength to support the weightof the vehicle and it preferably should be capable of withstanding evengreater force.

More recently, minimum performance criteria have been developed -by theSociety for Automotive Engineers for rollover protective systems, and atest is used to simulate the applied stress during rollover. This testhas become an industry standard for testing rollover protective systems.It is, of course, desirable to have a uniform test so that availablesystems may be compared and improved. One such test procedure forestablishing whether a system exhibits the required performance criteriais described in the SAE technical report J320a.

It is desirable that a rollover protective system be designed such thatit can be mounted to existing vehicles as well as to new vehicleswithout re-design of the basic vehicle frame, as this is not practical.In addition, it is desirable from the point of view of design andmanufacturing economy that the same basic system approach, includinginterchangeable elements of the system, be used on as many of thedifferent types of construction vehicles as is possible. Not only arethe economies of mass production thereby realized, but even moreimportantly, as experience is gained with system operation for differenttypes of vehicles, the system can be improved and thereby affordedgreater protection to an operator.

It is, however, difficult to achieve a uniform system forrolloverprotection which is capable of being secured to the manydifferent types of construction vehicles because of the widely varyingsituations encountered. For example, the operator is not always locatedin the same part of a vehicle, and the different vehicle designs includeframes with stronger and weaker por tions that may be located at thevarying locations about the operators position.

In the SAE test mentioned above, a hydraulic ram is positioned againstthe top of a rollover protective system which is mounted to a vehicle,and the ram is extended to apply a force at the top of the rolloverprotection system in a direction transverse of the intended direction oftravel of the vehicle. Thus, a predetermined force simulating the stressapplied to a vehicle during rollover is first applied. After this forceis removed, a predetermined weight is deposited on top of the rolloverprotective system to simulate the applied stress if the vehicle werecompletely turned over. In addition, in order for a proposed system tobe acceptable, the total deflection of the protective system must besuch that no part of the rollover protective system will enter theso-called critical zone. The critical zone is an imaginary volume inwhich the 95th percentile man (when ranked in increasing size) outfittedin artic clothing so as to take up a maximum space, would occupy. Moreinformation concerning the critical zone may be found in SAE TechnicalReport 1397.

The rollover protection system of the instant invention includes anintegral superstructure formed from upright corner column members joinedat their upper ends by longitudinal and transverse horizontal members.At each upper corner of the superstructure, a novel gusset memberinterconnects the three coincident superstructure members in a mannersuch that stress applied to any one of these members will be transferredto the others under smooth transition to minimize buckling. The bases ofthe superstructure upright column members are anchored by means ofvibration mounts or rigid connections to brackets which are attached tothe vehicle frame. The interaction of the superstructure, mounts,brackets, and vehicle frame to resist deflection during the SAE test oractual rollover is a very important aspect of the present system. Allelements of the system cooperate to transfer stresses to the vehicleframe in a smooth transition to protect against failure of any componentwhether in normal operation or in the event of an accident.

The upright column members of the superstructure are placed outside ofthe corners of the critical zone and thereby leave an open field ofvision for the operator in the intended direction of travel of thevehicle. Further, the superstructures are adapted so that panels may bemounted to it and thereby fully enclose the operators station andprotect the operator against harsh environments, as in US. Pat. No.3,572,819.

Another advantage of the instant inventive system is that the same basicelements may be used for a number of different vehicle types, eachhaving different frames, and yet it will be assured that the rolloverprotective system will pass the above-mentioned SAE test withoutintrusion of the superstructure into the critical zone. That is, thepresent invention permits a designer to con sider the various parametersof each individual vehicle type (such as the strength of the frameworkthe protective system is to be mounted on, the availability of space,the strength of the brackets attached to the vehicle framework and thestrength of the roll bars themselves) and to design a system from alimited number of basic elements which are interchangeable betweensystems wherein the applied simulated rollover stress will betransmitted in smooth transitions to the strongest part of the vehicleframe with a minimum of deflection of the superstructure.

Other features and advantages of the present invention will be apparentto persons skilled in the art from the following detailed description ofalternative embodiments wherein identical reference numerals will referto like parts in the various views.

THE DRAWING FIG. 1 is a rear perspective view of a crawler tractorequipped with a rollover protective system, according to the presentinvention;

FIG. 2 is a side elevational view of the rollover protective system ofFIG. 1;

FIG. 3 is a rear elevational view of the rollover protective system ofFIG. 1;.

FIG. 4 is a fragmentary rear view of the tractor of FIG. 1 showing therollover protective system after stress;

. FIG. 4a is a close-up rear view of the front mounts for the rolloverprotective system after stress has been applied.

FIG. 5 is an enlarged fragmentary perspective view, partially brokenaway, of a mount for the rollover protective system;

FIG. 6 is a vertical sectional view of the mount of FIG. 5 showing theassociated column in a deformed state;

FIG. 7 is a fragmentary perspective view of the rollover protectivesystem as viewed from below and showing the gusset means whichinterconnect the various columns and beams;

FIG. 8 is a perspective view of the inside of one of the gusset means ofFIG. 7;

FIG. 9 is a fragmentary vertical sectional view of one upper corner ofthe rollover protective system;

FIG. 10 is a view similar to FIG. 9 but of a modified form of structureutilizing tubular as contrasted to formed beams and a modified form ofgusset;

FIG. 11 is a view similar to FIG. 10 but showing various elements in thecondition assumed under stress;

FIG. 12 is a front perspective view of a scraper equipped with theinventive rollover protective system;

FIG. 13 is a front elevation view of the rollover protective system ofFIG. 12 under stress;

FIG. 14 is an enlarged fragmentary perspective view, partially brokenaway of one type of mount for the rollover protective system of FIGS. 12and 13;

FIG. 15 is a vertical sectional view of the mount of FIG. 14 but in thecondition assumed under stress;

FIG. 16 is a side elevational view of the rollover protective system ofFIG. 15; and

FIG. 17 is a front and rear elevational view of the rollover protectivesystem of FIG. 12.

DETAILED DESCRIPTION Referring now to FIG. 1, reference numeral 20generally designates a crawler tractor equipped with the rolloverprotective system of the present invention. As already indicated, theinvention has application to a wide variety of construction vehicles.For convenience of reference, we have referred to such equipment asconstruction vehicles or simply tractors because particular emphasis hasbeen placed on the safety of operators of graders, scrapers, haulers,and tractors as well as those pieces of self-propelled equipment whichare used in allied industries such as logging, mining, materialhandling, and the like. It will be appreciated therefore that theinvention relates in its broader aspects to rollover protective systems,and it is not limited to use with any particular type of workingvehicle.

The tractor 20 is equipped with a chassis 21 supporting an engine 22,operators station or seat 23 and controls 24. The chassis or frame 21also supports the inventive super-structure generally designated 25 andthe entire piece of equipment is propelled by crawlers designated 26. Itwill be noted that the operators seat 23 is completely circumscribed bythe perimeter of the superstructure 25 and further, the superstructure25 is so arranged and constructed so that under extreme stress, noportion thereof enters the critical zone occupied by the operator anddescribed above.

The superstructure 25 includes four upright columns or legs denotedrespectively 27-30 which are also seen in FIGS. 2 and 3. The front(i.e., in the direction of forward vehicle travel) legs are designatedby the numerals 27 and 28 for the right and left legs respectively. Therear legs are designated 29 for the rear right leg and 30 for the rearleft leg. Each of the columns 27-30 may be a tubular column of generallysquare cross section which, for most vehicles can be either 4 X 4 inchesor 5 X 5 inches with the wall thickness being about 3/8". Each of thelegs or column members 27-30 are attached at their bases to the frame21.

Each column 27-30 is connected to the frame 21 through mounting meansgenerally designated 31 and which can be seen in FIGS. 5 and 6 relativeto the column 29. The general arrangement and additional details of themounting means can be seen in co-owned US. Pat. No. 3,560,019.

In FIGS. 5 and 6 (the column being under lateral stress and designated29 in the latter), the mounting means 31 includes a sleeve 32 which isequipped with a perimetrically enlarged bottom flange 33 providing ashoulder 34. The column 29 is received over the upper portion of thesleeve 32 and is secured against the shoulder 34 as by a weld at 35.

Extending upwardly from the base 21 is a bayonet mount 36 equipped withan enlarged flanged base 37. The base 37 is secured to a bracket 38 bywelding as at 38a. The bracket 38 will be described in greater detailpresently. The sleeve 32 has a vertically extending channel 39 which isdefined by four walls which are inwardly inclined at their upper ends.The walls of the bayonet mount 36 are correspondingly tapered as at theportion designated 40 in FIG. 6.

A cushioning member 41 of rubber or other suitably resilient materialextends around the mount 36 above the flange 37, and is interposedbetween the base flange 33 of the sleeve 32 and the flanged base 37 ofthe bayonet mount 36.

The sleeve 32 (and hence the column 29) is secured to the bayonet mount36 by means ofa locking element 42. The element 42 extends throughaligned passages in the sleeve 32 and the column 29 and through avertically elongated slot 43 in the bayonet mount 37. The slot 43 isequipped with a lining 44 of rubber or similar resilient material alsoslotted as at 45.

As illustrated in FIGS. 2 and 3, the columns 27-30 of the superstructure25 have their bases securely attached to the frame 21 by means ofbrackets, the forward brackets being designated by reference numeral 40and the rear brackets being designated 40a. It is considered one of theprimary advantages of the present invention that the same elements maybe used to achieve a superstructure which will pass the SAE test andthereby achieve the economies of interchangeable parts, while adaptingthe system to vehicles of different types. For example, in the crawlerillustrated the chassis or frame 21 is equipped with heavy longitudinalside frames extending along either side of the operators station, and,therefore, in this construction, it is desirable to secure thesuperstructure 25 to these longitudinal beams. Other vehicle types mayhave stronger frames at different locations, thereby requiring slightlydifferent brackets, but nevertheless enabling the use of the samegeneral configuration of superstructure being described. In the case ofthe front columns 27 and 28, the bracket 40 includes a verticallyelongated plate 40b bolted to the frame 21 and including an outwardlyextending horizontal pedestal 40 0 (see FIG. 3), the lower side of whichis braced against the vertical plate 40b by means of a brace 40d. Thus,the base flange 37 of the bayonet mount 36 is welded to the top surfaceof the pedestal 40c.

The base portions of rear columns 29 and 30 are connected to the frame21 by similar brackets generally designated 40a in FIG. 2. In thisinstance, a pedestal 40e receives the base flange 37 of the bayonetmount 36, and this pedestal 40e is bolted to a similar plate 40f which,in turn, is welded to a vertical plate 40g which is secured to thelongitudinal beams of the frame 21.

The columns 27-30 are connected at their upper ends by four horizontalbeams, two of which are extended longitudinally of the vehicle and aredesignated 41a and 41b in FIG. 7, interconnecting respectively the topsof the beams 27, 29 and 28, 30. There are also two transverse beamsdesignated respectively 41c and 41d in FIG. 7. At each upper corner ofthe superstructure, an upright column, a longitudinal beam and ahorizontal beam are connected together into an integral, unitaryjunction by means of corner gussets, generally designated 42 which canbe seen in perspective in FIG. 7 from beneath the superstructure and inFIG. 8 from a position above the gusset with the gusset not attached tothe superstructure.

Each of the corner gussets 42 as seen in FIG. 7 interconnects an uprightcolumn, a longitudinal beam and a transverse beam of the superstructure.

In plan view, the superstructure top for the embodiments of FIGS. 1-7 issubstantially square, and a canopy plate 43 including depending sideflanges 43a and 43b overlies the longitudinal beams 41a and 41b.

For the embodiment of FIGS. l-3, we have found it advantageous toincline the rear columns 29 and 30 (see particularly FIG. 2). In theillustration given, the inclination is of the order of degrees from thevertical. Although this inclination is not critical, it is useful intransferring stress to the strongest portion of the vehicle frame incertain instances. This example further illustrates the flexibility ofthe inventive system in drawing the load to the strongest part of theframe for a particular vehicle through the use of the shortened rearcolumns 29 and 30 which cause the rear portion of the superstructure tobe stiffer and hereby draw the load to the vehicle at locations justbehind the operators station where the frame is best able to withstandthe load for this type of vehicle.

The showing in FIGS. 4 and 4a is a superstructure suitable for use witha Caterpillar C9G crawler tractor wherein identical reference numeralsrefer to like elements for the embodiment of FIGS. l-3. The embodimentof FIGS. 4 and 4a, however, has been stressed, and the results will bediscussed below.

The critical zone is diagrammatically illustrated in FIGS. 2 and 3 bythe chain line C.

Turning now to the corner gussets 42, each gusset includes three struts,designated 45, 46 and 47 in FIG. 8. Each of the struts 45-47 can be seento define a channel, denoted respectively 45a, 46a and 47a. Each channelis defined on two adjacent sides by tabs, denoted 45b, 45c, 46b, 46c,47b and 47c.

The gusset 42, as illustrated, is a solid, integral piece,

preferably made according to conventional metalforming techniques froman integral piece of metal for strength and integrity. Thus, the tabs45c and 46b are joined by means of a connecting brace 45d. Similarly,the tabs 46c and 470 are connected by a brace 46d and the tabs 45b and47b are connected by a brace 47d. The braces 45d, 46d and 47d, are, inturn, connected together by means of a triangular median plate 48. Thelongitudinal edges of the braces 46d and 4711' which are not joined tothe plate 48 are provided with triangular web portions 49 and 50 toprovide additional support between the upstanding column member and thetransverse and longitudinal beams connected by the gusset 42. The axesof the three channels 450, 46a and 47a defined by the struts 45-47 forthe embodiment of FIG. 8 extend in mutually perpendicular direction. Thedownwardly extending channel 47a would, of course, be slightly modifiedto accommodate the inclination of the rear upright columns 29 and 34).Similar gussets can be adapted to beams of round or rectangular crosssections. The primary function of the gusset 42, as already mentioned,is to interconnect the intersecting transverse and longitudinal beamswith the upper end of one of the columns in such a fashion that anyapplied stress will be transmitted from the upper beams to the column ina smooth transition so that the stress may be borne by the frame of thevehicle and there will be only a minimum of deflection of thesuperstructure. This smooth transition of applied stress to the uprightcolumns is not impeded by inclining the upright column relative to thechannels 45a, 46a, thereby permitting the same gusset configuration tobe used on superstructures for different vehicles. In addition to theabove-mentioned manner of manufacturing the gusset 42, it may equallywell be fabricated by welding individual parts together or it may becast.

Reference is now made to FIG. 9 and to the forward right-hand corner ofthe superstructurei.'e., at the intersection of beams 41a and 41c withcolumn 27. In that comer, the strut 45 receives the beam 41a, the strut46 receives beam 41a, and the strut 47 is attached to the column 27.Thus, the plate 47d forms a diagonal reinforcing and connecting memberbetween beam 41a and column 27 for force transmission. In like fashion,it will be seen that the plate 46d provides a diagonal brace betweenbeam 41c and column 27. Lastly, the plate 45d serves as a diagonal bracebetween the beams 41a and 410. Each of the tab portions associated witha particular strut is welded to its associated column or beam, as thecase may be. It will be observed that each tab is relatively small incross sectional area at its distal end, and this area graduallyincreases toward the junction with its associated diagonal brace. Thisgradual increase in size effects a smooth transition of stresses underload to the gusset and thence to a column. Other shapes may be used forthe tab, but it should preferably exhibit this characteristic. As aconsequence, the triangular plate 48 provides a load transmittingelement extending between and secured to each pair of intersectingstructural members, and each of the diagonal braces, sometimes referredto as flanked portions, of the corner gusset is an integral extension ofthe triangular center plate which serves as a base common to all threeintersecting structural members.

Referring to the gusset located diagonally opposite the one justdiscussed, it will be noted that the web 49 extends between column 30and beam 41d, and the web 50 extends between column 30 and beam 41b.These two triangular webs fill in the spaces between the diagonal braces46d and 47d, and the two intersecting structural members (beam andcolumn) which these plates join. The webs have their edges welded to thecorresponding structural members, thus adding further reinforcement tothe corner interconnection.

The triangular webs 49 and 50 are shown in the corner gusset 42 providedat the left rear corner in FIG. 7. It is also possible to have a similartriangular web extending between the struts 45 and 46 in a horizontalplane. However, usually the superstructure is equipped with a canopy, asmentioned, which serves as a reinforcing corner web for the twointersecting beams at each corner.

Due to the shape in which the corner gusset 42 is constructed, it iseconomical from the standpoint of the amount of material actuallyrequired in its production, and its interconnection to the associatedbeams and columns does not present any particular problem. What is moreimportant, however, is that it provides for an equalized and smoothtransition of stress between all connected structural members. The tabsby which the gusset is secured to the beams and columns act as stressreducing elements in distributing the load along these structuralmembers while the triangular median plate 48, adjoining all of thestruts, tends to distribute the load about all three intersectingstructural members. Thus, a smooth transition in section strength ismade possible between all of the intersecting members and the cornergusset provides good load carrying capability in all directions insteadof only a single direction. By this means we are able to provide astructure wherein a stress loading applied to one structural member isnot absorbed by that particular structural member but instead istransmitted to other structural members. Instead of having the stressmainly resisted by a particular column, the stress is distributed bymeans of the beams and corner gussets to the other three columns andthence to the vehicle frame thereby making for a stronger and much moreeffective rollover protection because the strongest portion of the framemay then bear the bulk of the load.

The same type of corner gusset may be employed in connection with theshowing in FIGS. 4 and 4a. The showing there is of a superstructureespecially suitable for a loader, only a portion of which is seen.Further, the illustration shows the loader after stress is applied inaccordance with the SAE test mentioned above.

In FIGS. 4 and 4a the overlying canopy is again designated by thenumeral 93 with the depending side flanges being designated 43a and 43b.Corner gussets are denoted 42, and it will be seen that the uprightcolumns 27-30 are all vertical and of about the same length.

The mounts 31 are similar to the mounting means already described, andthey connect the bottom portions of the upright columns 29 and 30 tobrackets designated 55 in FIG. 4. The brackets 55 are supported bylaterally-extending members 56 which, in turn, are supported by anglebrackets shown partially in dashed line and designated 57.

The forward upright columns 27 and 28 are secured to lateral rails 58which are supported, in turn, by plates 59. The plates 59 are braced bymeans of inclined braces 60 against reinforced sidewalls 70. Thesidewalls 70 are, in turn, secured to the frame of the vehicle. For thisembodiment, the rear mounts for the upright columns 29, 30 are intendedto bear a greater rollover stress than forward columns.

Referring now to FIG. 4, the critical zone may be diagrammaticallyillustrated by the dashed line C, as viewed from the rear. When alateral force, indicated by the arrow F is applied to the top of thesuperstructure, the force is transmitted to the beams and columns of thesuperstructure, held together by the gussets 42 and then to thesupporting brackets and the frame of the vehicle. The superstructurewill deflect in the manner illustrated in FIG. 4 whereby the transverseand horizontal beams will be translated to the right, thereby bendingthe upright columns 29, 30 in the manner shown. However, none of thesuperstructure will enter into the critical zone C. In addition, it willbe observed that the forward vision of an operator in the direction ofintended travel of the loader is not impaired in the slightest by thesuperstructure. Thus, an operator during rollover is enclosed on allsides of his person by means of the superstructure (as distinguishedfrom some systems wherein a canopy is cantilevered over an operator fromthe rear), and the inventive system permits adaptation of the basicsystem of upright columns and transverse and longitudinal beams tovehicles of many different designs while insuring that the appliedrollover stress is transmitted in uniform transition from the horizontalbeams to the vertical columns and thence to that portion of the vehicleframe which is best suited to bear the rollover stresses.

Turning now to FIG. 10, there is shown a view of an upper corner of arollover protective system, similar to FIG. 9, except that the canopy 43is missing. In this embodiment, a longitudinal beam 65 is shown to havea tubular shape, and a similar transverse beam 66 is connected to theend of the beam 65. An upright corner column is designated 67. A cornergusset, generally designated by reference numeral 68 interconnects thebeams 65-67, and it includes first and second tabs 69 and 70 for weldingto the column 67 as well as similar tabs for welding to the beams 65 and66. The principal difference of the gusset 68 from that previouslydescribed is in the inclusion ofa smoothly curved plate 71interconnecting the three struts which are generally designated byreference numeral 73, 74, and respectively. The struts secured to theupper beam 65 and 66 do not have tabs for welding to the sides of thosebeams, that is, each strut has only a lower tab and these are designatedrespectively 73a and 75a which weld respectively to the lower surfacesof the beams 66 and 65 Under lateral stress, the embodiment depicted inFIG. 10 deforms in a manner illustrated in FIG. 11 wherein the verticalcolumn 67 and the beam 65, although forced together, are braced apart bythe smooth curvature of the corner gusset 68, this bracing, of course,affords a smooth transition of applied stress among all of the threeinterconnecting superstructure members 65-67.

Turning now to FIG. 12, there is shown a front perspective view of ascraper which is provided with a rollover protective system constructedaccording to the present invention. The scraper includes a rear bowlgenerally designated 75 and a forward cab 76. The operators station isgenerally designated by reference numeral 77 and it is located forwardlyand above the forward wheels 79. A horizontal frame platform 80 isconnected to the forward chassis of the scraper.

The rollover protective system for the scraper includes a superstructuregenerally designated 81 which includes four generally upright columns82, 83, 84 and 85 as well as two longitudinal upper beams 86 and 87 andtwo transverse beams 88 and 89. The operator's station is normallyenclosed by means of panels secured to the superstructure 81, but thepanels have not been illustrated in order to more clearly show thesuperstructure. At the forward upper portion of the operator stationthere is a windshield 90.

The corners of the upper beams and upright columns are connected withcorner gussets generally designated by reference numeral 92 which aresimilar to the corner gussets 42 which have been previously described inconnection with FIG. 8 particularly.

Turning now to FIGS. 16 and 17, the rear corner column 84 is seen tocomprise an upper generally vertical portion 84a and a lower inclinedportion 8412. A gusset 95 braces the upper and lower portions 84a, 84bof the beam 84. The gusset 95 is similar to the previouslydescribedgussets 92 in its attachment to the intersecting beamed portion and itsability to effect a smooth transition of forces between interconnectedbeam members.

The gusset 95 includes an upper tab 97 which is welded to the forwardsurface of the vertical beamed portion 84a and a lower tab 98 which iswelded to the lower beam portion 8412. An inclined interconnecting plate99 (see FIG. 12) interconnects the tabs 97, 98. First and second sideportions (only one of which is shown in FIG. 16 and is designated 100)extend from the plate 99 for engaging the forward surfaces of both beamportions 84a, 84b to brace them against buckling.

Turning now to FIG. 17, the forward vertical columns 82, 83 are furtherinterconnected by means of a horizontal forward beam 103 which is bracedrespectively against the upright columns 82, 83 by two pairs ofright-angle gussets which are generally designated by reference numeral104, all of which may be identical. The right-angle gussets 104 aresingle to the justdescribed gusset 95 for interconnecting and bracingtwo intersecting beams, except that the end tab portions (designated 106and 107) extend in perpendicular directions. The gusset 104 is otherwisemodified to accommodate a right-angle intersection of the two beams.

As will be further observed from FIG. 17, the rear right corner column85 is inclined outwardly relative to the front corner beam 82, and ashas already been mentioned, it is considered one of the features of thepresent invention that such beams may be angled either to connect thesuperstructure at its base to the strongest portion of the vehicleframe, or, if desired, to lend an aesthetic appearance to the operatorscab.

The two rear beams 84, 85 may be further braced by means of a horizontalbeam partially shown in FIG. 17 and designated by reference numeral 110.The beam 110 will come, of course, connected to the upright columns bymeans of gussets, one of which is partially shown in FIG. 17 anddesignated 111.

The bottom of the column 85 is connected to a portion of the framedesignated 112 of the vehicle by means of a mount 113 which is similarto the previous ly-described mounts 31, illustrated in FIGS. and 6. Thebottoms of the remaining three upright columns 82, 83 and 84, may beconnected to the vehicle frame by an alternative type of mount which isgenerally designated by reference numeral 115 and shown in greaterdetail in FIGS. 14 and 15. The mount 115 is an antivibration mount, aswas the prevoiusly-described mount. The mount 115 has an advantage inlow cost and simplicity over the previously-described mount.

Turning then to FIGS. 14 and 15, the mount 115 is shown for connectingthe upright forward column 83 to a bracket 116 which, in turn, isconnected to the main frame of the vehicle. The mount includes anintegral pedestal generally designated by reference numeral 118 andincluding an upper crown 119 of generally uniform rectangular horizontalcross section with rounded comers, and a base 120. The outer peripheryof the base 128 is approximately equal to the dimension of the outerperiphery of the upright column 83, and it is welded as at 121 to thebracket 116. The lower end of the column 83 is spaced above the uppersurface of the base of the mount, as indicated by the distance 5 in FIG.114, for reasons which will be explained pres ently.

The crown portion 119 of the mount is provided with a transverse channel125 which receives a flexible filler 126. The filler 126 is providedwith a bore 127 which receives a shaft 128. The bore 127 of the filler126 may be elongated slightly in a vertical direction as illustrated inFIG. 15, if desired. The bolt 128 is provided with a hexagonal head 129,and the other end of the bolt 128 may be threaded to receive a nut insecuring the upright column 83 to the pedestal 118.

At the top of the crown 119 there is a cap 130 which includes aperipheral bumper member 131. The cap 130 may also be of a hard flexiblematerial, and it serves as a cushion for the interior of the tubularcolumn 83 when it is deflected as shown in FIG. 15. As illustrated inFIG. 15, the lower portion of the column, when deflected, will tilt asshown, and the spacing S permits a uniform tilting of the column aboutthe shaft of the axis 128 without binding. The cushion or bumper 131 aswell as the flexible filler material 126 reduce vibration duringoperation.

Turningnow to FIG. 13, there is shown a test stand for testing therollover protective system superstructure for the scraper shown in FIG.12 after the lateral force has been applied. The test stand includes anoutwardly extending beam 135 which is secured to it by means of bolts136 and is cantilevered in a slightly upwardly inclined position toaccommodate the superstructure 81.

The applied simulated rollover stress force may be applied in thedirection of the arrow 138.

With the present invention, then, there is provided a rolloverprotective system which is capable of being fabricated to fit theindividual needs of each vehicle type. Primary among these needs is anability to transmit any applied rollover stress, whether actual orsimulated, to that portion of the vehicle frame which is best able towithstand it. Secondly, the rollover protective system, having as itdoes a superstructure interconnected with the novel gussets illustratedand described, is able to transmit the rollover stress in orthogonaldirections and in smooth transition, thereby to distribute the appliedrollover stress to all portions of the frame equally.

Having thus described in detail a preferred embodiment of the inventivesystem, persons skilled in the art will be able to modify certain of thestructure which has been illustrated and to substitute equivalentelements for those which have been described while continuing topractice the principle of the invention; and it is, therefore, intendedthat all such modifications and substitutions be covered as they areembraced within the spirit and scope of the appended claims.

1. A rollover protective system for vehicles comprising: at least fourgenerally upright columns spaced at the corners of an operators station;a plurality of generally horizontal beams interconnecting the upper endsof said columns to provide a superstructure; gusset means for rigidlyinterconnecting each column with its associated beams, each gusset meanscomprising an integral corner gusset having three struts extending ingenerally perpendicular relation, each strut including members welded toan associated beam or column, and rigid median plate meansinterconnecting all of said struts to provide a smooth transition ofapplied stress from said beams to said columns; and mounting meanspivotally interconnecting the lower end of each column to the frame ofsaid vehicle when said structure is in assembled relation with saidvehicle.

2. The structure of claim 1 wherein said members of each strut comprisefirst and second tabs extending in generally perpendicular planes andadapted to be welded to adjacent sides of an associated beam or columnhaving a generally rectilinear cross section.

3. The structure of claim 2 wherein said rigid median plate means ofeach strut comprises a diagonal brace plate extending between each pairof struts, and a generally triangular median plate connected to theinner edge of each of said brace plates.

4. The structure of claim 2 wherein each median plate means of saidstruts comprises diagonal brace plate means extending between at leasttwo pairs of said struts and a smoothly curved median plate connected tothe inner edge of each of said brace plates.

5. The structure of claim 1 wherein at least one of said columns isshorter than the others and inclined relative to a vertical lineextending perpendicular to its associated beams to thereby draw any loadapplied to said protective structure to a stronger part of the vehicleframe.

6. The structure of claim 1 wherein said protective structure is adaptedto receive enclosing panels thereby to enclose the operators station andprovide the opera tor with environmental protection.

7. A rollover protective structure for vehicles comprising: a pluralityof generally upright columns spaced about an operator's station; aplurality of generally horizontal beams interconnecting the upper endsof said columns to provide a superstructure; gusset means for rigidlyinterconnecting each column with a pair of associated beams, each gussetmeans including an integral corner gusset having three struts extendingin generally perpendicular relation, each strut including a pair of tabmembers welded to an associated beam or column, and rigid median platemeans interconnecting all of said struts to provide a smooth transitionof applied stress from said beams to said columns; and mounting meansinterconnecting the lower end of each column to the frame of saidvehicle when said structure is in assembled relation with said vehicle.

1. A rollover protective system for vehicles comprising: at least fourgenerally upright columns spaced at the corners of an operator''sstation; a plurality of generally horizontal beams interconnecting theupper ends of said columns to provide a superstructure; gusset means forrigidly interconnecting each column with its associated beams, eachgusset means comprising an integral corner gusset having three strutsextending in generally perpendicular relation, each strut includingmembers welded to an associated beam or column, and rigid median platemeans interconnecting all of said struts to provide a smooth transitionof applied stress from said beams to said columns; and mounting meanspivotally interconnecting the lower end of each column to the frame ofsaid vehicle when said structure is in assembled relation with saidvehicle.
 2. The structure of claim 1 wherein said members of each strutcomprise first and second tabs extending in generally perpendicularplanes and adapted to be welded to adjacent sides of an associated beamor column having a generally rectilinear cross section.
 3. The structureof claim 2 wherein said rigid median plate means of each strut comprisesa diagonal brace plate extending between each pair of struts, and agenerally triangular median plate connected to the inner edge of each ofsaid brace plates.
 4. The structure of claim 2 wherein each median platemeans of said struts comprises diagonal brace plate means extendingbetween at least two pairs of said struts and a smoothly curved medianplate connected to the inner edge of each of said brace plates.
 5. Thestructure of claim 1 wherein at least one of said columns is shorterthan the others and inclined relative to a vertical line extendingperpendicular to its associated beams to thereby draw any load appliedto said protective structure to a stronger part of the vehicle frame. 6.The structure of claim 1 wherein said protective structure is adapted toreceive enclosing panels thereby to enclose the operator''s station andprovide the operator with environmental protection.
 7. A rolloverprotective structure for vehicles comprising: a plurality of generallyupright columns spaced about an operator''s station; a plurality ofgenerally horizontal beams interconnecting the upper ends of saidcolumns to provide a superstructure; gusset means for rigidlyinterconnecting each column with a pair of associated beams, each gussetmeans including an integral corner gusset having three struts extendingin generally perpendicular relation, each strut including a pair of tabmembers welded to an associated beam or column, and rigid median platemeans interconnecting all of said struts to provide a smooth transitionof applied stress from said beams to said columns; and mounting meansinterconnecting the lower end of each column to the frame of saidvehicle when said structure is in assembled relation with said vehicle.